server-skynet-source-3rd-jemalloc/include/jemalloc/internal/bitmap_inlines.h

#ifndef JEMALLOC_INTERNAL_BITMAP_INLINES_H
#define JEMALLOC_INTERNAL_BITMAP_INLINES_H

#ifndef JEMALLOC_ENABLE_INLINE
bool bitmap_full(bitmap_t *bitmap, const bitmap_info_t *binfo);
bool bitmap_get(bitmap_t *bitmap, const bitmap_info_t *binfo, size_t bit);
void bitmap_set(bitmap_t *bitmap, const bitmap_info_t *binfo, size_t bit);
size_t bitmap_ffu(const bitmap_t *bitmap, const bitmap_info_t *binfo,
    size_t min_bit);
size_t bitmap_sfu(bitmap_t *bitmap, const bitmap_info_t *binfo);
void bitmap_unset(bitmap_t *bitmap, const bitmap_info_t *binfo, size_t bit);
#endif

#if (defined(JEMALLOC_ENABLE_INLINE) || defined(JEMALLOC_BITMAP_C_))
JEMALLOC_INLINE bool
bitmap_full(bitmap_t *bitmap, const bitmap_info_t *binfo) {
#ifdef BITMAP_USE_TREE
	size_t rgoff = binfo->levels[binfo->nlevels].group_offset - 1;
	bitmap_t rg = bitmap[rgoff];
	/* The bitmap is full iff the root group is 0. */
	return (rg == 0);
#else
	size_t i;

	for (i = 0; i < binfo->ngroups; i++) {
		if (bitmap[i] != 0) {
			return false;
		}
	}
	return true;
#endif
}

JEMALLOC_INLINE bool
bitmap_get(bitmap_t *bitmap, const bitmap_info_t *binfo, size_t bit) {
	size_t goff;
	bitmap_t g;

	assert(bit < binfo->nbits);
	goff = bit >> LG_BITMAP_GROUP_NBITS;
	g = bitmap[goff];
	return !(g & (ZU(1) << (bit & BITMAP_GROUP_NBITS_MASK)));
}

JEMALLOC_INLINE void
bitmap_set(bitmap_t *bitmap, const bitmap_info_t *binfo, size_t bit) {
	size_t goff;
	bitmap_t *gp;
	bitmap_t g;

	assert(bit < binfo->nbits);
	assert(!bitmap_get(bitmap, binfo, bit));
	goff = bit >> LG_BITMAP_GROUP_NBITS;
	gp = &bitmap[goff];
	g = *gp;
	assert(g & (ZU(1) << (bit & BITMAP_GROUP_NBITS_MASK)));
	g ^= ZU(1) << (bit & BITMAP_GROUP_NBITS_MASK);
	*gp = g;
	assert(bitmap_get(bitmap, binfo, bit));
#ifdef BITMAP_USE_TREE
	/* Propagate group state transitions up the tree. */
	if (g == 0) {
		unsigned i;
		for (i = 1; i < binfo->nlevels; i++) {
			bit = goff;
			goff = bit >> LG_BITMAP_GROUP_NBITS;
			gp = &bitmap[binfo->levels[i].group_offset + goff];
			g = *gp;
			assert(g & (ZU(1) << (bit & BITMAP_GROUP_NBITS_MASK)));
			g ^= ZU(1) << (bit & BITMAP_GROUP_NBITS_MASK);
			*gp = g;
			if (g != 0) {
				break;
			}
		}
	}
#endif
}

/* ffu: find first unset >= bit. */
JEMALLOC_INLINE size_t
bitmap_ffu(const bitmap_t *bitmap, const bitmap_info_t *binfo, size_t min_bit) {
	assert(min_bit < binfo->nbits);

#ifdef BITMAP_USE_TREE
	unsigned level = binfo->nlevels - 1;
	size_t lg_bits_per_group = (LG_BITMAP_GROUP_NBITS * (level+1));
	size_t bits_per_group = 1LU << lg_bits_per_group;
	size_t bits_per_group_mask = bits_per_group - 1;
	unsigned group_nmask = (min_bit & bits_per_group_mask) >> (level *
	    LG_BITMAP_GROUP_NBITS);
	bitmap_t group_mask = ~((1LU << group_nmask) - 1);
	bitmap_t group = bitmap[binfo->levels[level].group_offset] & group_mask;
	if (group == 0LU) {
		return binfo->nbits;
	}
	size_t bit = ffs_lu(group) - 1;

	while (level > 0) {
		level--;

		lg_bits_per_group = (LG_BITMAP_GROUP_NBITS * (level+1));
		bits_per_group = 1LU << lg_bits_per_group;
		bits_per_group_mask = bits_per_group - 1;

		group = bitmap[binfo->levels[level].group_offset + bit];
		size_t cur_base = bit << lg_bits_per_group;
		if (cur_base < min_bit) {
			group_nmask = (min_bit & bits_per_group_mask) >> (level
			    * LG_BITMAP_GROUP_NBITS);
			group_mask = ~((1LU << group_nmask) - 1);
			group &= group_mask;
		}
		if (group == 0LU) {
			/*
			 * If min_bit is not the first bit in its group, try
			 * again starting at the first bit of the next group.
			 * This will only recurse at most once, since on
			 * recursion, min_bit will be the first bit in its
			 * group.
			 */
			size_t ceil_min_bit = (min_bit +
			    BITMAP_GROUP_NBITS_MASK) & ~BITMAP_GROUP_NBITS_MASK;
			if (ceil_min_bit != min_bit && ceil_min_bit <
			    binfo->nbits) {
				return bitmap_ffu(bitmap, binfo, ceil_min_bit);
			}
			return binfo->nbits;
		}
		bit = (bit << LG_BITMAP_GROUP_NBITS) + (ffs_lu(group) - 1);
	}
	assert(bit < binfo->nbits);
	return bit;
#else
	size_t i = min_bit >> LG_BITMAP_GROUP_NBITS;
	bitmap_t g = bitmap[i] & ~((1LU << (min_bit & BITMAP_GROUP_NBITS_MASK))
	    - 1);
	size_t bit;
	do {
		bit = ffs_lu(g);
		if (bit != 0) {
			return (i << LG_BITMAP_GROUP_NBITS) + (bit - 1);
		}
		i++;
		g = bitmap[i];
	} while (i < binfo->ngroups);
	return binfo->nbits;
#endif
}

/* sfu: set first unset. */
JEMALLOC_INLINE size_t
bitmap_sfu(bitmap_t *bitmap, const bitmap_info_t *binfo) {
	size_t bit;
	bitmap_t g;
	unsigned i;

	assert(!bitmap_full(bitmap, binfo));

#ifdef BITMAP_USE_TREE
	i = binfo->nlevels - 1;
	g = bitmap[binfo->levels[i].group_offset];
	bit = ffs_lu(g) - 1;
	while (i > 0) {
		i--;
		g = bitmap[binfo->levels[i].group_offset + bit];
		bit = (bit << LG_BITMAP_GROUP_NBITS) + (ffs_lu(g) - 1);
	}
#else
	i = 0;
	g = bitmap[0];
	while ((bit = ffs_lu(g)) == 0) {
		i++;
		g = bitmap[i];
	}
	bit = (i << LG_BITMAP_GROUP_NBITS) + (bit - 1);
#endif
	bitmap_set(bitmap, binfo, bit);
	return bit;
}

JEMALLOC_INLINE void
bitmap_unset(bitmap_t *bitmap, const bitmap_info_t *binfo, size_t bit) {
	size_t goff;
	bitmap_t *gp;
	bitmap_t g;
	UNUSED bool propagate;

	assert(bit < binfo->nbits);
	assert(bitmap_get(bitmap, binfo, bit));
	goff = bit >> LG_BITMAP_GROUP_NBITS;
	gp = &bitmap[goff];
	g = *gp;
	propagate = (g == 0);
	assert((g & (ZU(1) << (bit & BITMAP_GROUP_NBITS_MASK))) == 0);
	g ^= ZU(1) << (bit & BITMAP_GROUP_NBITS_MASK);
	*gp = g;
	assert(!bitmap_get(bitmap, binfo, bit));
#ifdef BITMAP_USE_TREE
	/* Propagate group state transitions up the tree. */
	if (propagate) {
		unsigned i;
		for (i = 1; i < binfo->nlevels; i++) {
			bit = goff;
			goff = bit >> LG_BITMAP_GROUP_NBITS;
			gp = &bitmap[binfo->levels[i].group_offset + goff];
			g = *gp;
			propagate = (g == 0);
			assert((g & (ZU(1) << (bit & BITMAP_GROUP_NBITS_MASK)))
			    == 0);
			g ^= ZU(1) << (bit & BITMAP_GROUP_NBITS_MASK);
			*gp = g;
			if (!propagate) {
				break;
			}
		}
	}
#endif /* BITMAP_USE_TREE */
}

#endif

#endif /* JEMALLOC_INTERNAL_BITMAP_INLINES_H */